How come it is legal for kids under 18-21 at a wedding, but not a bar?

Your question was asked in Yahoo Answers Canada so I will give the Canadian answer (not sure if the same applies to the US).

It all depends on the type of liquor license held by the establishment. As others have pointed out, the wedding venue typically serves food and the primary function is not as a bar, so the type of license usually allows minors. It would be a similar license that a restaurant would hold.

For those types of establishments that hold cabaret, tavern, beverage room or lounge licenses, minors are prohibited from entering, it is not up to the establishment.

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There are a few other types of licenses like eating establishment license, special event license, special Premise license, etc. Each of these have their own requirements and allowances.

@Perse - minors in Ontario can only consume alcohol that is provided to them by a parent or someone in lawful custody while in a residence or private place. The above still applies in regards to which liquor serving establishments can allow minors to be present.

Regardless of age, the person providing the alcohol is responsible anyone they supply liquor to, whether it is a homeowner in a private party or a bartender at a bar.

In the U.S., the legal drinking age in most states is 21. If you are under 21 you can't be served alcohol at a bar or a wedding.

A wedding venue, or bartender at a private party is subject to the same fines as a bar for serving a minor. If the reception is on private property (like a backyard wedding), the owners of the property are liable.

Also its not illegal in the U.S. for anyone 18-21 to enter the establishment, until 9PM. Any time before 9PM anyone is welcome, regardless of age. There are also some clubs and bars that are ages 18 & up, but its still illegal to serve alcohol to any person under the minimum drinking age.

Most wedding reception venues and halls are not bars, therefore anyone of any age is welcome. But they still have same regulations for who can be served alcohol.

In Australia it depends on the type of liquor licence the venue holds :)

I think If food is served, under 18's are allowed in with a parent or guardian :)

Not sure of the laws exactly where you live....but where I live, you must be of a certain age to drink in public places (bars, clubs, restaurants) but may legally drink underage at a private event (weddings, house party, etc;) The reason for this is at a private event, the liability if you do something stupid while underage and drunk is on the host or the homeowner, they are responsible for your actions, while at the bar, nobody is there to watch out for you and the bartenders do not want to be liable for the risk that you get alcohol poisoning, drive drunk, etc which statistically you are much more likely to do than someone older.

It's considered a restaurant. Kids can obviously enter a restaurant where liquor is being served. Technically a kid is allowed in a bar, it's the establishment that bans it to avoid legal problems.

Children under 18 are allowed in restaurants aren't they? And most bar tenders at weddings would know to ask for ID if they thought a minor was trying to drink.

I don't know about Canada, but in the United States only 15 states ban alcohol consumption by minors. Federal law only prohibits sale to minors. 31 States allow for minors to consume alcohol at private venues with parental consent.

By that logic, why are kids allowed in restaurants? I don't think it's the law that prevents them from entering bars, just the bar owners not wanting to risk going to jail for accidentally serving alcohol to a minor.

Because a wedding isn't about getting hammered and going home with a prostitute. Well...for most families anyhow! LOL

Seriously? It's a family event.